Water-impact fuse



March 24, 1936. H, J, NlCHOLs 2,035,186

WATER IMPACT FUSE INVE TOR /fw/ .Mm/S.

ATTORNEY March 24, 1936. J, NlCHOLs 2,035,186

WATER IMPACT FUSE Filed Oct. 22, 1932 2 Sheets-'Sheet 2 BYWM ATTORNEY lil Patented Mar. 24, `1936 l' UNITED STATES PATENT oFFicE (Granted under the act oi' March 3, 1883, as amended April 30, 1928; 370 0. G. 757) My invention relates to improvements upon the type of fuse disclosed in my Letters Patent No. 1,446,764. The object of my present invention is to improve and simplify the construction and operation of such fuses, as well as to render the same more efficient and safe under all circumstances, and to render the same substantially less expensive in production.

Other objects of my invention will appear from the following specification and the foregoing objects and their resulting advantages will be made more apparent therein.

In the drawings illustrating my invention, Fig. 1 is a central, longitudinal sectional view of a fuse embodying my invention showing the parts in their normal position;

Fig. 2 is a view similar to Fig. 1, but showing the parts in the position in which they detonate or deflagrate the charge with which the fuse may be associated;

Fig. 3 is a central longitudinal sectional View of a further simplied and more inexpensive fuse embodying my invention and adapted for attachment to the nose of bombs and pyrotechnic devices, and illustrating the parts in their normal positions;

Fig. 4 is a view similar to Fig. 3, but showing the p-arts in the position in which they are adapted to detonate or deflagrate the charge in the bomb or pyrotechnic device with which such fuse is associated.

In the drawings, in which like parts are indicated by the same reference characters, the species of my invention illustrated in Figs. 1

and 2 is adapted for attachmentto projectiles to be fired from guns, while the species shown in Figs. 3 and 4 is designed for attachment to bombsV as well as pyrotechnic devices that may be dropped from aircraft into, or upon the surface of, the sea and for other purposes.

Referring to the species of my invention shown in Figs. 1 and 2, 5 represents the fuse stock which, in the instance shown, constitutes an integral part of the projeetileonose plug, or if desired, the same may be a separate portion screwed into or otherwise secured to the projectile nose plug.

The fuse stock 5 is bored axially to form a cylindrical chamber 6 in which a piston 1 is slidably mounted. The forward portion of the fuse stock 5 is provided with a bore 8 preferably oi.

larger diameter than, and communicating with, the bore 6, which bore 8 is provided with internal screw threads adapted to receive a cylindrical externally threaded rnose plug 9. The-plug 9 has an axial opening I0 extending therethrough provided with an enlarged outer mouth which is normally closed by a sealing disk II inserted into and against the shoulder of the mouth where the disk is rmly secured in place by a ring I2. 5 The ring I2 is provided with an outwardly ilar- 'ing central opening whose smallest diameter preferably conforms to vthe diameter of opening I0 in plug 9. The plug 9 is provided in its front face with a groove 9a which forms a relatively 10 end of piston 'I is a rigid piston rod 24 whose pro- 20 jecting end'is provided with an enlarged head 28 from which extends firing pin 25. Normally, the Y inner face of head 28 rests against the base of a cup 2| having formed through the center thereof an opening 22 normally occupied by ring pin 25. 25

In the instance shown, the outer diameter of cup 2| conforms to the internal diameter of the bore 6, and the edge of cup 2| rests against the outer face of primer retainingring I6 which is peripherally rabbeted at its forward end to engage 30 shoulder 6a in the bore of fuse stock 5. Primer holding ring I5 having projection I5a upon its forward face surrounding a shouldered recess adapty ed to receive the primer charge or pellet, is inserted into stock 5 with a primer gasket 20 of 35. paper, fibre, thin copper or other suitable material, substantially cup-shaped in form adapted to be pressed between said projection I5a and the opening through ring I6, which gasket 20 holds in place the primer pellet I8. Threaded or otherwise secured in the rear end of the bore in stock 5, is a plug I4 to hold rings I5 and I6 and disk 2| firmly in the positions shown in Figs. 1 and 2. The plug I4 is provided with a. central, longitudinall opening I1 extending through ring I5 into communication with the primer pellet I8, Iso that when the'pellet is detonated the flame .will pass through opening I1 to the charge exposed at or suitably adjacent the mouth of the opening I1. f

Thefuse stock 5 is provided with screw threads upon` its inner end`which are adapted to engage in corresponding threads in the projectile.

Plugs 9 and I4 are each provided with longi- 55 tud'inal openings |4a,.as shown in Figs. 1 and 2, adapted to receive the prongs of a spanner wrench for screwing them into place when the same are provided with screw threads for their securement.

The strength of the cup 2| is such that when theV fuse stock 5 as shown and described is secured into the nose of a projectile and such projectile is firedfrom a gun, that the shock of firing will not overcome the resistance of the cup to the head 28 of piston 1 and that cup` 2| will, under such circumstances, hold the piston I in place with the head of piston 'I against the plug 9.

The sealing disk may be' formed of metaL moisture proof lfibre or other desiralclle':material of such strength in its connedyposition'fthat the' same is not ruptured by the-shock' 'of firing.-.1the

projectile nor during its flight thrughthe' air.' and yet the disk must be Vsulic'siently frail tobe ruptured upon impact ofthe noseof. the projec- 'tile with water. forced through the inwardly converging opening in ring l2, disrupts the sealing disk liyows through opening l in plug 9 and against vthe head of piston 1. If the head of piston 'l were flat, or otherwise conformed to the shape of the juxtaposed surface of plug 9 the area oftheopen-` ing IU would limit the initial areaof the thrustA of the impacted water upon the head of piston 1. However, thelrecess in'the piston head 1 surrounding the conical projection 26, whose apex is centrally disposed relative to opening I0, permits the water, which rushes at great velocity through opening I0, to be spread uniformly about the conical projection 26 and to be deected by the curved base of the recess in the piston head, which reversed impacted water strikes against the interior surface of plug 9. The area of the jet of water againstthe head of piston 1 being of greater area than opening I l) exerts substantially greater force against the piston initially than it would if the face of piston 'l'were not so shaped. `The head 28 of' piston rod 24 is thus driven through the cup 2| by dishing the center of the cup and enlarges the opening therethrough, as shown in Fig. 2. 'I'he diameter of opening 22 in cup 2| whereby the lesser diameter of piston rod 24 is freed from engagement With the wall of opening 22 and the firing pin 25 is permitted to strike,

`with the full force of the water against the piston head, the primer gasket-2U' and indent the same A as shown in Fig. 2 to detonate the primer pellet mouth of opening i I8 whose products are violently projected through opening I1 to explode the charge adjacent the In the form of my invention disclosed in Figs. 3 and 4, the fuse stock 5a is formed conical with an integral cylindrical wall 5b on its base enclosing a cupped recess 5c whichA is adapted to receive the forward end lof the body of a bomb, pyrotechnic device or the like.- Where apyrotechnic device is to be provided with my fuse, such body is preferably formed of wood or other materialy of sucient buoyancy to float the entire device upon the water, in which case the fuse stock 5a and its attached metallic parts are of such weight as to maintain the pyrotechnic device vertically in the water with its fuse stock end or nose downward; the body portion being of such length 'and provided near its upper end with the usual vertical, laterally extending ns to maintain the device vertical While falling through the air after being released from an aircraft.

Openings 5e are provided at intervals inthe wall 5b for the insertion of screws or nails for the attachment of fuse stock 5a to the bomb body.

Upon such impact.- water isv tion of fuse stock 5a is a bore 6a whose outer portion is of increased diameter from its inner portion, forming a shoulder 6b at their junction.

Tube 30, Whose exterior diameter is adapted to be pressed into smaller bore 6a of fuse stock 5a, is provided at its forward end with a flange- 3| adapted to engage shoulder 6b. Freely slidable within the tube 30 is a piston 'la having on its head a central conical projection 26a surrounded by a wall 21a of a structure and function substantially the same as that described for piston 1 inconnection with Figs. 1 and 2. The opposite end of piston "la is similarly formed with a central conical projection 26h surrounded by an outer wall 2lb. The walls 21a, 2lb form the skirt of the piston whose outer surfaceis adapted to slide freely within the bore of tube 30. The rear end of 4tube 30 is provided withan enlarged bore 32 provided with shoulder 33 intermediate the norv mal bore of tube 30 and bore 3,2. Against shoulder 33 is adapted to be firmly seated a. washer 3.4 of

. bre or metal.

, of tube 30 is provided with an axial opening Ila extending therethrough whose forward aring mouth IIlb terminates in a shouldered cavity adapted to receive a primer pellet |8a. This primer pellet cavity and mouth Hb are formed in a central projection 36 of member 35. The primer pellet |8a'is adapted to be held firmly in place in its cavity by a cupped primer gasket a, preferably of bre, thin copper or other suitable material having flange 20h. 'I'he gasket 20a is adapted to be pressed in place over projection 36 with its bottom wall contacting the primer pellet |8a. The thus constructed and assembled primer supporting member 35 is inserted with its projection 36 surrounded by gasket 20a through the opening in\washer 34 with the flange 2Gb of gasket 20a clamped between the adjacent face of washer 34 and shoulder 31 ofvmember 35 with a spring 38 surrounding projection 2Gb and the body of gasket 28a and extending between the adjacent faces of piston fla and washer 34. In this position member 35 is secured by spinning or otherwise forming the rear end of tube 30 over the tapering end 39 of member 35. The rear end of member 35 is provided with a recess 49 adapted to receive a primer tube extending thence into the body of the bomb or pyrotechnic device for communicating the products of the detonated primer pellet Ia to the explosive or pyrotechnic component respectively of the bomb or pyrotechnic device.

'I'he tube 30 is closed by a sealing disk Ila extending continuously over the flanged end 3| of tube 3D and is there firmly sealed by a plug 9c whose outer smooth surface is adapted to t i snugly within the bore 6a of fuse stock 5a where plug 9c is permanently secured in rm contact against disk a by spinning or otherwise formafter being launched from the aircraft. Im-

pacted water will'enter mouth Ib, thence through opening I Ba, where it will disrupt disk I la, Thereupon such impacted water will act'upon thevhead of piston 1a, aspreviously described in connection'with piston 1, end will drive piston 1a inwardly, compressing spring 38- until conical-projection 2Gb vstrikes with substantial force and indents the hea'd of cup gasket 2nd and thereby .detonates the primer pellet I8a Whose products are dischargedI through opening Ila to occasion the detonation or deflagration of the explosive or of the United States for governmental purposes;

pyrotechnic content of the bomb or pyrotechnic device enclosed in bodyd.l

In connection with Figs. 3 and 4, it will be noted that the cupped disk 2| of Figs. 1 and 2 and its function are absent from the structure shown in connection with the limprovement of my invention illustrated in Figs. 3 and 4. This is forthe reason that there is no substantial shock to the release of a bomb or pyrotechnic device .that there is incident tothe firing of a projec- A tile from a gun. Consequently, in the form of my invention illustrated in Figs. 3 and 4 the' spring 38 is under all circumstances, able to hold the piston 'la from impacting and detonating theA primer pellet |811r exceptwhen the bomb,` pyrotechnic or other device associated therewith impacts water. l 'A The herein -described manufactured or used by or for the Government without the payment of any royalty thereon.

What I claim is:

1. In a fuse for projectiles, bombs and. pyrotechnic devices, the combination of a fuse stock, a primer supporting' member rigidly carried -by said stock, a piston slidably mounted in said stock forwardly of said member, a firing pin carried by said piston, a primer supported by said member, a plug secured in the nose of said stock forwardly of said piston and provided with an opening therethrough adapted to communicate with the head of said piston, and sealing means between-said plug and said piston 'for sealing said opening, whereby, when the nose of said stock impacts with water, impactedwater will enter said opening, disrupt said sealing means l and act upon said piston to drive said firing pin into detonatingcontact with the primer.

A an opening associated with the head of said piston, and impact releasable means for sealing said opening whereby, when the nose o f said stock impacts with water, impacted water will enter said opening, unseal said sealing means, deform said deformable means an'd move said piston to drive said firing pin into detonating contact with the primer.

3. In a fuse for projectiles,'bombs and pyrotechnic devices, the combination 'of' a fuse stock, a primer supporting member rigidly carried by said stock, a piston slidably mounted in said stock forwardly of said member, a firing pinA connected to said piston, a` primer supported by said member, deformable means normally holding said pin away from said primer, a'plug secured in the nose of said stock forwardly of said piston and inventionvv may be.

aosrg'ise'fI l3 provided with an opening therethrough vto communicate with the head of said piston,and impact releasable means for sealing the mouth of said opening.

- 4. In a fuse for projectiles, bombs and pyro- .5'

technicdeviceathe combination of a fuse stock provided with a longitudinal opening in its nose', a primer supporting member rigidly carried by said stock, a primer carried by said member, im-

pact releavsable means for closing said opening, 10

and means normally rigidly carried by said stock intermediate said member and.' .said opening adapted to detonate or defiagrate the primer when actuated by the force of impactedY water entering said opening. 15

5. In a fusev for projectiles, bombs and pyrotechnic devices, the combination of a fuse stock provided with a Alongitudinal opening in its nose, a member adapted to support a primer rear-A wardly of said opening, a primercarried thereby, 20`

a pistonslidable intermediate said member and said opening', a rearward projection from said piston, a firing pin on said projection, deformablemeans rigidly carried by said stock in contact with the end of said projection and adapted 25 to be deformed -thereby to move said pin to detonate orA deflagrate the primer by theforce of an impacted medium `entering said opening and acting upon said piston.

` 6. In a fuse for projectiles, bombs and pyro- 30 technic devices, the combination of a fuse stock provided with a longitudinal opening in its nose, a member supporting a primer rearwardly of said opening, a primer carried thereby, a piston slidable intermediate said member and vsaid 35 openingeand provided with a rearward projection, a firing pin on the free end of said projection, deformable means rigidly carried by said stock in contact with the end ofsaid projection and having a hole therethrough of lesser diameter than 40 said projection adapted to be occupied by said pin, said projection being adapted to be driven through said hole to move said pin to detonate the primer by the force of an impacted medium entering said opening and actingon said piston. 45

7. In a fuse' for projectiles, bombs and pyrotechnic devices, the combination of a fuse stock having a longitudinal opening therethrough enlarged at opposite ends, means mounted in the rearward enlargement of said opening and sup- 50 porting a primer, a primer in said means, a plug securedin said rearward enlargement adapted rigidly to hold said means therein, said plug and means, being provided with openings adapted to register with each other and with the primer, a 55 pistonnot normally slidable in the unenlarged portion of said opening, a ring pin connected to4 said piston to detonate or deagrate the primer, deformable means for normally securing said piston from rearward movement, and 60 a' separate plug secured in the forward enlargement of said opening and adapted to secure said piston from forward movement and having a hole therethrough.

8. In a fuse for projectiles, bombs and pyro- 65 technic devices, the combination of a fuse stock rhaving a longitudinal opening therethrough,

means rigidly mounted in said stock and adapted to carry a primer in said opening, deformable means rigidly mounted in said opening in advance of said primer means and provided with a hole therethrough, and a piston not normally adapted to slide in said opening in advance of said deformable means and provided with a projection having an enlarged head and a firing pin projecting from said head, said pin being normallyv in said hole and said head being larger than said hole and impinging against said deformable means.

10. In a fuse for projectiles, bombs and pyrotechnic devices, the combination of a fuse stock having a longitudinal opening therethrough, means rigidly mounted in said stock and adapted to carry a primer in said opening, a primer in said means, deformable means rigidly mounted in said opening in advance of said primer and provided With a hole therethrough, a piston not normally adapted to slide in said opening in advance of said deformable means, a -projection from said piston having an enlarged head, a, firing pin projecting from said head, said pin being normally in said hole and said head being larger than said hole and in contact with said deformable means, a plug secured in the front of the fuse stock opening normally contacting the head of the piston and provided with an opening therethrough, and impact releasable means for closing said opening in said plug.

11. As an article of manufacture for a fuse for projectiles, bombs and pyrotechnic devices, a piston having a projection extending from one end, an enlarged head on said projection, a pin extending from said head, a recess in the remaining end of said piston, and a conical projection in said recess.

12. In a fuse for bombs and pyrotechnic devices, the combination of a fuse stock having an opening therethrough having a shoulder near its rear end, a tube in said opening and having a shoulder on its forward end cooperating with said flrstshoulder, apiston slidable in said tube and having a vfiring pin projecting therefrom, primer supporting means secured in said tube rearwardly of said piston, a spring in said tube said stock, a deformable cup member interposed between said firing member and said primer mounting member constituting the sole safety device of the fuse, and an opening positioned forwardly of and in communication with the head of said firing member, whereby, when said stock impacts with a soft target, the substance of the target will enter said opening and drive said firing member into exploding contact with said primer.

14. In a fuse for projectiles, bombs, and pyrotechnic devices, the combination of a fuse stock, a'primer mounting member immovably carried by said stock, a primer firing member provided with a head and a firing point slidably mounted in said stock, and a deformable cup member interposed betiveen said firing member and said primer mounting member, said deformablecup member constituting the safety device of said fuse. v

15. In a'fuse for projectiles, bombs and pyrotechnic devices, the combination of a fuse stock, a primer, a primer mounting member immovably carried by said stock, a primer ring member provided'with a head, a stem, and a firing point, and a deformable cup member provided with a central hole through which projects part of the ring member, said cup member being adapted to prevent contact of said firing point with said primer until impact with the target occurs.

. 16. In a fuse for projectiles, bombs, and pyrotechnic devices, in combination, a fuse stock, a primer, a primer mounting member immovably mounted in said stock, primer firing means including a head, a firing point and an intermediate member, and a deformable cup member providedwith acentral hole adapted normally to pass the ring point but not the intermediate member of said 'firing means, said cup member comprising the safety device of the fuse.

HARRY J. NICHOLS. 

